The public Internet has become an extremely popular source of information and vehicle for communications. Each day, millions of people log on to the numerous available web sites. Nearly every major company as well as many small companies and even individuals have web sites which allow the general public to visit. Every indication leads one to believe this trend will only continue to grow.
Physically, the Internet is a huge, global network spanning nearly 100 countries and comprising a great number of academic, commercial, government, and military networks. Each of the computers on this network uses the data network protocol TCP/IP (Transmission Control Protocol/Internet Protocol). Some users have direct access to the Internet. In other words, these users have computer systems which are connected via dedicated transmission facilities connecting the users at access points provided by Internet service providers, typically at speeds of 1,536 mbps and above.
Many other users, however, must connect to the Internet through an Internet service provider (ISP) via circuit switched access at speeds below 56 kpbs. An ISP can receive communications from a user's computer through a modem connected over the Public Switched Telephone Network (PSTN). The ISP owns equipment that provides an interconnection from a circuit-switched network to a packet switched network. There is a need to make the connection from the PSTN to the Internet more efficient.
One common method of Internet connectivity is over the Public Switched Telephone Network (PSTN). The PSTN was designed for voice traffic for an average hold time of about three minutes. Internet traffic using the voice network, on the other hand, has an average hold time of about thirty-five minutes and is constantly growing. For example, the 1997 average hold time of twenty minutes has grown to thirty-eight minutes in about a year. The problem is further exacerbated by the fact that peak traffic periods of the Internet and Voice traffic overlap. These factors cause congestion at high concentration points in the network and an inefficient use of the existing network, which is not optimized for Internet traffic.
FIG. 1 illustrates a block diagram of a common method of connection from computer (PC) 10 to Internet 12. The computer 10 is coupled to a modem 14. The modem generates signals which can be transported along the PSTN 16 where the necessary switching occurs so that a connection is made to a network access server (NAS) 17. In particular, PSTN 16 utilizes a number of switches including class 3 and class 5 switches. The PSTN may be operated by a local telephone company, e.g., a regional Bell operating company (RBOC), and NAS 17 is controlled by an Internet Service Provider (ISP). The ISP also owns computer hardware such as routers and servers which are linked to the Internet 12.
One of the problems associated with the system of FIG. 1 is the high cost of communications between the switch (such as switch 22 in FIG. 2) and NAS 17. This connection is usually made using a POTS (plain old telephone service) or ISDN (integrated services digital network) connection. These systems typically use channel associated signaling and tend to be very expensive.
FIG. 2 illustrates an alternative prior art system which will lower the cost of communication between computer 10 and Internet 12. In this case, NAS 17 has been located physically near to switch 22, which is typically a class 5 switch. Since the cost of the link between NAS 17 and switch 22 is distance sensitive, total cost can be lowered by locating the two components closely.
This same concept applies where more than one local exchange carrier controls the switches 15, 22. In that case, communications from modem 14 go first to incumbent local exchange carrier (ILEC) and from there to competitive local exchange carrier (CLEC). For example, the ILEC may be a local telephone company such as one of the RBOCs (regional Bell operating companies). The CLEC may be another carrier such as MCI or AT&T.
In the prior art, the class 5 switch causes network congestion. With increasing hold times, this congestion may cause impacts to community related (e.g., public) services such as 911 if the carrier does not closely monitor switch capacity and utilization.
Another disadvantage of the prior art is that it makes very inefficient use of class 5 switch 22. The class 5 switch has many capabilities which are not utilized or required by the system of FIG. 1. While the system of FIG. 2 has advantages over that of FIG. 1 because of the reduced communication cost, it still requires a class 5 or similar switch and does not address the problem of network congestion.